Methods performed by nodes, and nodes

Abstract

A method performed by a first node in a wireless communication system is provided. The method includes receiving, from a base station, a configuration message including layer 1/layer 2 (L1/L2) triggered mobility (LTM) candidate information associated with a LTM candidate cell, wherein the LTM candidate information includes first information on an early uplink (UL) synchronization procedure; performing the early UL synchronization procedure with the LTM candidate cell based on the LTM candidate information; performing a L1 measurement on the LTM candidate cell; and transmitting, to the base station, a report message for the L1 measurement.

What is claimed is: 
     
         1 . A method performed by a user equipment (UE) in a wireless communication system, the method comprising:
 receiving, from a base station, a configuration message including layer 1/layer 2 (L1/L2) triggered mobility (LTM) candidate information associated with a LTM candidate cell, wherein the LTM candidate information includes first information on an early uplink (UL) synchronization procedure;   performing the early UL synchronization procedure with the LTM candidate cell based on the LTM candidate information;   performing a L1 measurement on the LTM candidate cell; and   transmitting, to the base station, a report message for the L1 measurement.   
     
     
         2 . The method of  claim 1 , wherein the LTM candidate information further includes second information on a LTM candidate identifier (ID) and third information on a physical cell identity (PCI). 
     
     
         3 . The method of  claim 1 , wherein the first information on the early UL synchronization procedure includes random access channel (RACH) configuration information for performing a random access procedure on the LTM candidate cell. 
     
     
         4 . The method of  claim 3 , wherein the first information on the early UL synchronization procedure further includes information of an UL carrier for a random access preamble transmission on the LTM candidate cell. 
     
     
         5 . The method of  claim 1 , further comprising:
 receiving, from the base station, a LTM command via a media access control (MAC) control element (CE); and   switching to a target cell based on the LTM command.   
     
     
         6 . The method of  claim 5 , wherein the LTM command includes timing advance (TA) information associated with the target cell. 
     
     
         7 . A method performed by a base station in a wireless communication system, the method comprising:
 transmitting, to a user equipment (UE), a configuration message including layer 1/layer 2 (L1/L2) triggered mobility (LTM) candidate information associated with a LTM candidate cell, wherein the LTM candidate information includes first information on an early uplink (UL) synchronization procedure;   receiving, from the UE, a random access preamble based on the LTM candidate information; and   receiving, from the UE, a report message for a L1 measurement.   
     
     
         8 . The method of  claim 7 , wherein the LTM candidate information further includes second information on a LTM candidate identifier (ID) and third information on a physical cell identity (PCI). 
     
     
         9 . The method of  claim 7 , wherein the first information on the early UL synchronization procedure includes random access channel (RACH) configuration information for a random access procedure on the LTM candidate cell. 
     
     
         10 . The method of  claim 9 , wherein the first information on the early UL synchronization procedure further includes information of an UL carrier for a random access preamble transmission of the UE on the LTM candidate cell. 
     
     
         11 . The method of  claim 7 , further comprising:
 transmitting, to the UE, a LTM command via a media access control (MAC) control element (CE),   wherein the LTM command is for configuring the UE to perform a LTM cell switch procedure.   
     
     
         12 . The method of  claim 11 , wherein the LTM command includes timing advance (TA) information associated with a target cell. 
     
     
         13 . A user equipment (UE) in a wireless communication system, the UE comprising:
 a transceiver; and   a controller configured to:
 receive, from a base station via the transceiver, a configuration message including layer 1/layer 2 (L1/L2) triggered mobility (LTM) candidate information associated with a LTM candidate cell, wherein the LTM candidate information includes first information on an early uplink (UL) synchronization procedure, 
 perform the early UL synchronization procedure with the LTM candidate cell based on the LTM candidate information, 
 perform a L1 measurement on the LTM candidate cell, and 
 transmit, to the base station via the transceiver, a report message for the L1 measurement. 
   
     
     
         14 . The UE of  claim 13 ,
 wherein the LTM candidate information further includes second information on a LTM candidate identifier (ID) and third information on a physical cell identity (PCI), and   wherein the first information on the early UL synchronization procedure includes random access channel (RACH) configuration information for performing a random access procedure on the LTM candidate cell.   
     
     
         15 . The UE of  claim 14 , wherein the first information on the early UL synchronization procedure further includes information of an UL carrier for a random access preamble transmission on the LTM candidate cell. 
     
     
         16 . The UE of  claim 13 ,
 wherein the controller is further configured to:
 receive, from the base station, a LTM command via a media access control (MAC) control element (CE), and 
 switch to a target cell based on the LTM command, and 
   wherein the LTM command includes timing advance (TA) information associated with the target cell.   
     
     
         17 . A base station in a wireless communication system, the base station comprising:
 a transceiver; and   a controller configured to:
 transmit, to a user equipment (UE) via the transceiver, a configuration message including layer 1/layer 2 (L1/L2) triggered mobility (LTM) candidate information associated with a LTM candidate cell, wherein the LTM candidate information includes first information on an early uplink (UL) synchronization procedure, 
 receive, from the UE via the transceiver, a random access preamble based on the LTM candidate information, and 
 receive, from the UE via the transceiver, a report message for a L1 measurement. 
   
     
     
         18 . The base station of  claim 17 ,
 wherein the LTM candidate information further includes second information on a LTM candidate identifier (ID) and third information on a physical cell identity (PCI), and   wherein the first information on the early UL synchronization procedure includes random access channel (RACH) configuration information for a random access procedure on the LTM candidate cell.   
     
     
         19 . The base station of  claim 18 , wherein the first information on the early UL synchronization procedure further includes information of an UL carrier for a random access preamble transmission of the UE on the LTM candidate cell. 
     
     
         20 . The base station of  claim 17 ,
 wherein the controller is further configured to:
 transmit, to the UE via the transceiver, a LTM command via a media access control (MAC) control element (CE), 
   wherein the LTM command is for configuring the UE to perform a LTM cell switch procedure, and   wherein the LTM command includes timing advance (TA) information associated with a target cell.